Combrbtatiolt door-lock



UNITED STATES PATENT oFFIcE. N

M. R. sTEPHENsoN AND o. EDWARDS, or BosToNQMAssAoHusETTs.

COMBINATION DooRfLocK.

Specification of Letters Patent No." 3,543, dated April 17, 1844;

To all 'whomz't may concern: y y Be it known thatwe, MARCUS R. STEPH- ENsoN and OLIVER EDWARDS, of Boston, in

the `county of Suffolk and State of Massachusetts, have invented a certainnew and useful l Improvement in Locks to be Applied to Bank-Vaults, Doors ofuSafes, &c.,

and that the following specification ofthe same, taken in connection with theaccompanying drawings, fully sets forth the: nature and principles thereof by which it may be distinguishedfrom others of like charf` acter. I

Figure l, represents the internal arrange ment of the lock to which our improvement is applied. ,y

A, is the main bolt, which has a series B, of sliding plates applied `to it, the said plates being kept in requisite position by means of the vproject-ions C, C, (1,0, from two vinner frames D, E, arranged within the lock as seen in the drawing. The main holt is guided within these frames, and is otherwise supported in `the usual manner.`

Itis represented in Fig. 2,'as detached from the lock and having a movable plate F, applied to it which rests and slides freely up and down ina wide space or groove Gr, formed in the bolt and ofthe width and depth of the plate. The stud H, which usually extends from the bolt, is, in this case applied to the sliding plate F,

and when placed in the lock, it extends through a horizontal slot I, of a sliding plate K, as seen in Fig. 3, which is a representation of the plate as placed upon the bolt. The other sliding plates of the series are arranged and operate in theusual manner. The sliding plate K, is to be elevated to the `proper position, by means of one of the bit-ts of the key, and when so raised,

as it must also carry the stud` H, and slid-` ing plate F,-up with it, the stud will be `in the position necessary to admit of the recession of the main bolt. `As the remaining slidingplates, in the meantime, have also been raised by the key, the bolt, on its recession, will "carry the stud with y it through the horizontal Vslots which connect the vertical slots of the different `slide plates B. From the above,`it will be seen, that, whenever" an attempt is made to pick a lock so constructed, it will first become necessary to raise the stud H, to a certain, or its correct position and to there maintain it until the slide plates can be elevated into theiryrespectivo positions, a process which same being for the purpose hereinbefore specified. y In` testimony that the above is a correct specification of our improvement `we have hereto set our signatures this eighth day of February in the year 1844.

MARCUS. R. STEPHENSON, OLIVER EDVARDS. I Witnesses: y

R; H. EDDY, JOHN NQBLE, 

